--- title: "Subfloor and Finish Floor Repair | Rancho Santa Margarita" description: "Rotted RV decking cut back to sound framing, trusses sistered, plywood bedded and sealed, then LVT or sheet vinyl laid. $210 per hour in Yorba Linda." focus_keyword: "subfloor and finish floor repair rancho santa margarita" canonical: https://ocrv.me/services/interior-remodeling-and-repair/flooring-repair-and-replacement/ kind: subService updated: 2026-07-29 source: OCRV Center --- # Subfloor and Finish Floor Replacement in Water Damaged RVs > A soft floor is almost never a flooring problem. It is **rotted decking** under it. Real repair cuts back to sound framing, **$750 to $9,500+** at $210 per hour. ## What does subfloor and finish floor repair involve on an RV? Subfloor and finish floor repair removes rotted decking down to sound framing, sisters or replaces damaged floor trusses, bonds in exterior grade plywood, reseals the underbelly, then lays new finish flooring. Rancho Santa Margarita owners bring soft floors to our Yorba Linda bays for this work regularly. - OSB decking fails faster and further than plywood does - The rot is always wider than the soft spot you can feel - Cabinets and sometimes a slide room must come out for access - Underbelly coroplast and insulation get replaced, not just taped ### Key facts | Item | Value | | --- | --- | | Price range | $750 to $9,500+ (6 to 40 labor hours at $210 per hour) | | Labor rate | $210 per hour (Body and paint department) | | Typical turnaround | 3 to 12 shop days (Drying time to a measured target is part of the schedule) | | Common sources | Shower pan, toilet flange, slide seal, entry threshold, water heater bay | | Written estimate | $150 (Credited in full against an authorized repair) | The call almost always starts the same way. There is a spongy patch in front of the shower, or near the entry step, or along the edge where the slide comes in, and the owner would like new flooring. New flooring is the last twenty percent of that job. The other eighty percent is the deck underneath, which has been absorbing water for somewhere between one and ten years and has lost most of its strength. An RV floor is a structural deck. Plywood or OSB spans steel or aluminum floor trusses, bolted and bonded to the frame, with insulation and a coroplast underbelly beneath it. When that deck softens it is not a cosmetic issue, it is a load path issue, and laying luxury vinyl over it produces a beautiful floor that flexes exactly as much as it did before. ## The floor is structure, and that changes everything An RV deck spans steel or aluminum floor trusses and is fastened and bonded to the frame. It carries you, your furniture, your water and everything you loaded into the coach. It also ties the sidewalls together at their base. So when a section softens, the consequence is not just an unpleasant feeling underfoot, it is a section of the vehicle no longer doing its job. Owners frequently ask whether they can just cover it. The honest answer is that covering a soft deck is spending flooring money to hide a structural defect, and the defect keeps progressing underneath the new material where nobody can see it. By the time it becomes undeniable, the repair includes the flooring that was just paid for. ## Why OSB decks fail worse than plywood decks Both materials rot. They do not rot the same way. Plywood is cross laminated veneers, so water tends to produce a defined soft zone that stops reasonably close to where the water was. OSB is compressed strands with adhesive, and once moisture gets into it the strands swell, the bond fails, and the failure travels along the panel much further than the wetting did. In practice that means an OSB deck with a toilet flange leak often needs an entire bay replaced where a plywood deck with the same leak needs a couple of square feet. It also means a probe feels different: plywood goes soft, OSB crumbles. We always replace in exterior grade plywood regardless of what came out, because putting the weaker material back into a location that has already proven it gets wet is not a repair strategy. - Plywood: defined soft zone, repair stays local - OSB: strand swelling travels well past the wet area - Probe feel differs, soft against crumbling - Replacement is always exterior grade plywood ## The five places the water usually comes from Shower pan flange separation is first. The pan holds water fine, but the joint where its flange laps behind the wall surround opens, and every shower sends a little water down behind the pan instead of into the drain. Toilet flanges are second, and they are easy to check because a toilet that rocks has already lost its bearing surface. Third is the slide floor seal, which lets rain track along the leading edge of an extended room. Fourth is the entry threshold, where sealant has failed at the most flexed and most trafficked part of the floor. Fifth is the plumbing bay, where a weeping fitting drips into a cavity that a coroplast underbelly then holds shut. We check all five before ordering material, because a deck replaced under an unresolved source will fail again on the same timescale. We simply do not start the deck until the water is dealt with. ## What has to come out to reach the deck Access is where the hours live. Factory sheet vinyl runs underneath cabinetry, so the deck under a vanity or a galley base is genuinely inaccessible until those boxes move. Fixtures come out, and on damage at a slide threshold the room itself sometimes has to be pulled to get a clean cut and a proper new bearing surface. That last item is the single biggest step change in cost on this page, and it is why the range runs as wide as it does. We establish at estimate whether a slide has to come out, and we say so plainly, because an owner comparing quotes deserves to know whether the cheaper one simply planned to work around the room. ## Choosing between LVT, sheet vinyl and marine carpet Luxury vinyl tile is what most owners want and it works well, provided it is installed with an understanding that a coach flexes and gets hot. Click lock floating installs need expansion room at every perimeter and at slide thresholds. Glue down handles flex better and is our default in high traffic and high heat areas, particularly on south facing units that sit in Orange County sun all summer. Sheet vinyl is what the factory used, and it has real advantages: one continuous piece with no seams for water to find, and it runs under cabinetry so nothing telegraphs. Marine grade carpet remains the sensible choice inside slide out floors, where a hard surface fights the seal every time the room moves. Most coaches end up with a mix, and the transitions between them are worth doing properly. **Finish floor options in a coach** | Material | Best location | Main limitation | | --- | --- | --- | | Glue down luxury vinyl tile | Main living areas and galley | Requires a flat, sound deck | | Click lock luxury vinyl tile | Bedrooms and low traffic areas | Needs expansion room at every edge | | Roll sheet vinyl | Wet bath and full floor OEM style | Cabinets must be off to install correctly | | Marine grade carpet | Slide out room floors | Wears at the seal contact line | ## Drying is part of the schedule, not a delay in it Once a deck is opened and the wet insulation is out, the surrounding structure still holds moisture. Framing, the bottom of a wall, the edge of a panel that was never going to be replaced. Bonding new plywood against material that is still wet puts the repair in a damp sealed cavity, which is precisely the condition that created the original problem. So the coach sits with air moving through the opened area until readings match a dry baseline taken elsewhere in the same unit. How long that takes depends on how much water was in there and on the weather that week. It is measured rather than guessed, and it is written into the schedule at estimate so nobody is surprised by a coach that appears to be sitting still while something important is happening to it. > **note:** If a quote for a soft floor has no drying time in the schedule, ask where it went. Sealing new decking over damp framing is the fastest way to buy the same repair twice. ## Floors, claims and the gradual damage exclusion This is the page where owners most often discover the difference between sudden and gradual. A pipe that burst last Tuesday is usually a covered loss. A shower flange that has been weeping since 2019 generally is not, because most policies exclude damage that develops over time from a maintenance condition. That is not a carrier being difficult, it is what the policy says. Where it gets worth documenting carefully is a floor damaged by a covered event: a storm that drove water past a seal, a collision that opened a seam, a slide that failed and let rain in. In those cases the moisture map, the photographs of the open deck and the truss condition are what support the claim. We capture all of it as a matter of course, whether or not a carrier is currently involved. > **insurance:** Photograph the deck while it is open. Once new plywood is bonded down, the evidence for what was under there exists only in whatever pictures somebody remembered to take. ## Cost $750 to $9,500+, based on 6 to 40 labor hours at $210 per hour. Written repair estimate is $150, credited in full against an authorized repair. All work is performed in shop. ## Questions and answers ### Can you lay new flooring over the soft area instead of replacing the deck? We will not. A soft deck is structure that has lost strength, and covering it means the flex stays, the seams over the weak area fail, and the rot keeps progressing where nobody can see it. The eventual repair then includes tearing out flooring that was just paid for. ### How much bigger is the damage than the soft spot I can feel? Consistently larger, and in OSB decking much larger. Softness you can detect by foot is the middle of the wet zone. We map with a moisture meter in a grid against a dry baseline elsewhere in the coach, then cut to a truss centre with sound material on both sides. ### My trailer has OSB decking. Do you put OSB back? No, we replace in exterior grade plywood every time. OSB strands swell and lose their bond once wet, so the failure travels far beyond the wetted area. Putting the weaker material back into a spot that has already proven it gets wet is not a repair, it is a delay. ### Does the slide room have to come out to fix the floor at the threshold? Sometimes, and it is the biggest single cost step on this work. Damage at a slide opening usually involves the truss under the threshold, and a clean cut with a proper new bearing surface is not achievable with the room in place. We establish this at estimate rather than mid job. ### Do you need to open the underbelly as well? Yes, whenever water has reached the cavity. Coroplast underbelly holds water in as effectively as it keeps road spray out, so wet insulation left in place keeps the deck damp indefinitely. We pull the wet material, dry to a measured target, then close with new sheet and insulation. ### Will insurance pay for a rotted RV floor? Usually not if the water arrived gradually from a maintenance condition, which most policies exclude. It often will when the floor was damaged by a covered event such as a storm, a collision or a failed slide letting rain in. Documentation taken while the deck is open is what supports the claim. --- Source: [OCRV Center](https://ocrv.me/services/interior-remodeling-and-repair/flooring-repair-and-replacement/). Last verified 2026-07-29.